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The electronic and magnetic properties of tetravalent-ion-doped La0.85Zr0.15MnO3 (LZMO) thin films that were epitaxially grown on SrTiO3 (STO) and MgO substrates were studied using temperature-dependent x-ray diffraction (XRD), x-ray absorption near-edge structure, x-ray linear dichroism, and x-ray magnetic circular dichroism at the Mn L3,2- and K-edge. XRD studies reveal that the LZMO thin films have compressive and tensile strains (along the c-axis) on the STO and MgO substrates, respectively. As the temperature is reduced from room temperature to below magnetic transition temperature, the preferentially occupied Mn majority-spin eg orbital changes from the in-plane dx2-y2 to the out-of-plane d3z2-r2 orbital for LZMO/STO, and vice versa for LZMO/ MgO. Experimental results suggest that the new hopping path that is mediated by the Mn2+ ions triggers a stronger d3z2-r2 orbital ordering of Mn3+ ions and enhances the ferromagnetic coupling between the Mn spin moments of t2g electrons in LZMO/STO, whereas the strong tensile strain stabilizes the dx2-y2 orbital by inducing lattice distortions of the MnO6 octahedra in LZMO/MgO. [ABSTRACT FROM AUTHOR]

X-ray absorption spectroscopy measurements have been performed to elucidate local electronic and atomic structures of orthorhombic 3d-transition metal-doped yttrium manganites (YMnO3) with chemical formulae YMn2/3Me1/3O3 (Me=Co, Ni, and Cu). The Mn L3- and K-edges x-ray absorption near-edge structure (XANES) demonstrate the direct substitution of Me2+ for Mn3+, so that the positive effective charge of Mn ions are increased. Me-doping is also found to induce substantial broadening of the Mn L3-edge feature, which suggests enhancement of the delocalization of Mn 3d eg subbands and conductivity. Local spin density approximation (LSDA)+U (Hubbard U parameter) calculations were used to understand their electronic structures. [ABSTRACT FROM AUTHOR]

The electronic structure and magnetic properties of Al-doped Fe3O4 films at various Al concentrations were investigated by Al and O K-edge x-ray absorption near-edge structure (XANES) and Fe L3,2-edge magnetic circular dichroism (MCD) measurements. The O K-edge XANES spectra reveal that the intensity of O 2p–Fe 3d hybridized states decreases linearly as the Al concentration increases, suggesting that nonmagnetic Al substitution reduces couplings of the O 2p with Fe 3d orbitals. The Fe L3-edge MCD spectra show that the intensities of MCD features decrease as the Al concentration increases, which suggests that Al substitution reduces the magnetic moments of Fe ions. The Fe L3,2 XANES spectra suggest the absence of mixed valence states in agreement with previous x-ray resonance scattering measurements. [ABSTRACT FROM AUTHOR]

This study performs O K- and Ti L[sub 3,2]-edge x-ray absorption near-edge structure (XANES) measurements and first-principles pseudopotential calculations for the electronic structures of ABO[sub 3]-type Pb[sub 1-x]Ca[sub x]TiO[sub 3] (x=0–1) perovskites. The features in the O K-edge XANES spectra are found to be contributed primarily by hybridization between O 2p and Ti 3d, Pb 6p, and Ca 3d orbitals. The O K-edge XANES spectra reveal that partial substitution of A cations, Pb, by Ca not only decreases O 2p–Pb 6p but also O 2p–Ti 3d hybridization. The Ti L[sub 3,2]-edge measurements find that the off-center displacement of Ti, and hence, ferroelectricity persist up to a Ca concentration between 0.3 and 0.4. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This study utilizes the Core Conflictual Relationship Theme Method (CCRT; Luborsky and Crits-Christoph, 1997) on process study of short-term counseling. The purpose was to evaluate the formation and variation of interpersonal conflicts presented by nine clients, so as to enhance the understanding of the core conflicts of each client and how these clients were influenced by short-term counseling. CCRT was conducted by two raters to analyze the content of core conflictual relationship themes. The raters started with taking a twenty-minute vignette from four tapes of the counseling sessions which were the 1st, 2nd, 11th and the 12th. A transcript was taken for each session and the raters searched for relationship episodes (REs) in it. Further, other main persons were identified in REs. Three components, including wish(W), response from others(RO), and response of self(RS) were investigated and analyzed. The raters calculated the appearance frequency of each component and transferred them into formulation of relationship theme in written language. The findings are as follows. (1) The interrater reliabilities between the two raters over W, RO, RS are significant (Kappa = .21-.82, P < .01) (2) The most frequently described other main persons in 201 REs were 'clleague' (N = 87, 43. 3%), the second 'self' (N = 42, 32.8%) and the third 'family members' (N = 41, 20. 4%). The first three described wishes were 'to assert self and be independent' (N = 66, 32.8%), 'to be close and accepted' (N = 48, 23.9%), and 'to be loved and understood' (N = 35, 17.4%) (3) The change of pervasiveness scores of each component in terms of positive and negative responses evaluated by t-test were found to decrease significantly in NRO (r = -2.73, p < .05). The score was most significantly decreased in 'rejecting and opposing' item (t = -3.83, p < .01). Conclusions and suggestions regarding application of the Core Conflictual Relationship Theme analytical and categorization methods in the Chinese context are presented.

Mouse liver cell lines that bear a stably integrated lactose operon repressor (lacI) gene and a Ha-ras gene linked to a lactose operator-containing SV40 early promoter were generated. When grown in medium containing more than 0.1 mM isopropyl beta-D-thiogalactoside (IPTG), the Ha-ras gene was induced up to 20-fold. Maximum induction of Ha-ras gene expression occurred after 12 h of exposure. The tumorigenicity of these cell lines in syngeneic mice was enhanced when the mice were maintained on drinking water containing 12.5 mM IPTG. Ha-ras gene expression in tumors was strongly induced in the presence of IPTG in vivo. Induction of Ha-ras gene expression in mice was consistently observed after 48 hr of exposure to drinking water containing IPTG. This system provides an approach for studying the function of oncogene in vivo as well as other genes of interest.

As p53 is transcriptionally inactive in COS-1 cells, we felt it would be interesting to study the relative time course of expression of nuclear p53 and the onset of S phase. Our results indicated that the expression of nuclear p53 lagged behind the onset of S phase in COS-1 cells. In addition, rapid nuclear expression of p53, probably resulting from nuclear translocation, occurred immediately after the addition of serum into COS1 cells. No such phenomena were found in B104-1 and BHK cells.